Look, I don't know what it's made of, or the specifics of the materials used. I know it's a bit more durable and harder than the standard silicone or resin erasers I've used prior to cleaning stone and ceramic sharpeners. And it works way better. Please note that I don't use the really strong erasers sold to remove rust from steel. They are hard on rocks and sticks.
Refrigerator Sharp SJ-XE59PMBE, beige
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Lansky 2D2C Diamond Ceramic Four: Ultimate Sharpening Solution for Precision
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USA Made Diamond Lapping Paste Polishing Compound 600 Grit Mesh 22-36 Microns For Rock Glass Metal Jewelry Resin Marble With High Concentration Of Diamond Powder By TechDiamondTools
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Sharpening stone Hatamoto HT0960, green
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